Carburetor



March 11, 193M. 7 ow 1,750,349

CARBURETOR File M r h 16, 1925 2 Sheets-Sheet 1 ,4/QCH/E G. DOM/ELL,

March 11, 1930. A. G. DOWELL 1, ,3 9

CARBURETOR Filed March 16, 1925 2 Sheets-Sheet 2 mumgwuentoz ARCH/E C;DOM/ELL.

Patented Mar. 11, 1930 UNITED STATES PATENT; OFFICE ARCHIE G. DOWELL, OFSAN DIEGO, CALIFORNIA, ASSIGNOR OF ONE-HALF TO FRED A. SUTHERLAND, OFSAN DIEGO, CALIFORNIA CARBURETOR Application filed March 16, 1925.

My invention relates to carburetors, particularly adapted for vaporizingfuel for internal combustion engines, and the objects of myinventionare: first, toprovide a carburetor of this class particularly suitablefor enabling the-useof fuel containing an abnormal quantity of waterwithout affecting the smooth operation of the engine with which it isconnected; second, to provide a carburetor of this class whereby theconventional vacuum tank and other auxiliary apparatus for drawing orforcing the fuel from the fuel tank to the carburetor is eliminated, thecarburetor serving as a vacuum fuel feed means for drawing the fuel fromthe fuel tank; third, to provide a carburetor of this class in which theair entering the carburetor for vaporizing the liquid fuel therein isuniformly distributed under the body of fuel in the 29 fuel receptacle;fourth, to provide a carburetor of this class adapted to break up anyspray or globules of fuel which may be caused by the passage of airthrough the body of the fuel; fifth, to provide a carburetor of thisclass in which the fuelafter being vaporized and mixed with a smallquantity of air is mixed in regulated quantities with a further supplyof air at the outlet of the vaporized fuel into the passage of thelatter supply of air; sixth, to provide a carburetor of this class whichis protected from backfire of the engine cylinders; seventh, to providea carburetor of this class which is applicable for and may be readilyinstalled on most internal combustion engines now in use; and eighth, toprovide a carburetor of this class which is simple and economicalofconstruction proportionate to its functions, durable, easy to adjust,operate, and one which will not readily deteriorate orget out of order.

.VVith these and other objects in view, as will appear hereinafter,myinvention consists of certain novel features of construction,combination and arrangement of parts. and portions, as will behereinafter described in detail and particularly set forth in theappended claims, reference being had to the accompanying drawings and tothe characters of reference thereon, which form a part ofthisapplication, in which: i

Serial No. 15,807.

Figurelis a sideelevational view of my carburetor, showing fragmentarilycertain connections thereof with an internal combustion engine; Fig. 2is an end elevational View thereof; Fig. 3 is a plan view thereof takenat 3-8 of Fig. 1; Fig. 4 is a sectional elevational View thereof, takenthrough 4.4 of Fig. 2, showing certain parts and portions in, elevationto facilitate the illustration; Fig. 5 is another sectional elevationalview thereof, taken through 55 of Fig. 1, also showing certain parts andportions thereof in elevation to facilitate the illustration, and 6 is atransverse sectional view thereof, taken through 66 of Fig. 5.

Like characters of reference refer to similar parts and portionsthroughout the several views of the drawings.

The preferred embodiment of my invention, as illustrated in thedrawings, consists essentially of a fuel receptacle 1, a cover 2 securedto the upper open end thereof, a fuel supply conductor 3, a fitting 4connecting said supply conductor with the interior of said receptacle, avalve member 5 for controlling the flow of fuel from said supplyconductor to said receptacle, a float 6 for actuating said valve member,an air conductor 7 secured transversely to the cover 2 and extendingbeyond the sides thereof, an air conductor 8 connected with the one endof the air conductor 7 for conducting air heated by the ex haustmanifold of the engine to the conductor 7, a plurality of air conductors9, 10, 11 and 12 connecting the one end of the conductor 8 with thelowerportion of the receptacle 1, a perforated plate 13 positioned at thelower end of-the receptacle 1 through which the conductor 9 extends, athrottle butterfly valve 14: positioned in the conductor 7 at the outletend thereof, a choke butterfly valve 15 also positioned in the conductor7, extensible link means 30, 81 connecting said lastmentioned valves, acheck valve 16 positioned at the passage connecting the interior of thereceptacle 1 with the interior of the air conductor 7, a needle valve 17for adjusting the flow of the vaporized fuel into the conductor 7 ,and avalve means for supplying additional air in regulated quantitiesto thevaporized fuel in the receptacle above the level of the liquid fueltherein.

The fuel conductor 3, connected with a fuel tank, not shown, isconnected, by means of the fitting 4, with the side and near the lowerportion of the receptacle 1, however, preferably above the normal fuellevel therein. The end of the fitting a connected with the receptacle 1is provided with an enlarged hole t and a valve seat 4;. In thisenlarged hole is reciprocally mounted the valve member 5 which isprovided at its outer end with a polygonally shaped portion 5, forpositioning the valve member centrally within the hole 1, and with aconically shaped valve portion 5 at its inner end, which is adapted toseat against the valve seat 4r".

The means for uniformly distributing air over the lower portion of thereceptacle 1, which consists of the perforated plate 13, is positionedagainst an annular member 19, which spaces said plate from the bottom ofthe receptacle. Near the edge of the plate 13 is provided a lug 13 towhich is secured, by means of a screw 20, pin 21 on which is pivotallymounted, at its outer lower edge, the hollow annular metal float 6. Atthe pivotal portion of said float is provided an extended valveactuating member or lug 22 which is adapted to engage the outer end ofthe valve member 5 or the portion thereof extending into the receptacle1, and force the same inwardly against its seat as the float 6 is raiseda predetermined distance at its free side.

At the one extended end of the large air conductor 7, securedtransversely to the upper side of the cover 2, is pivotally mounted thehollow annular portion 8 of the hot air conductor 8 which extends to theexhaust manifold or pipe E, the end of the conductor 8 in engagementwith the exhaust n'ianifold or pipe being fringed or otherwise spacedtherefrom to permit hotair surrounding said manifold or pipe to be takenin through said conductor. The portion of the air conductor 7 aroundwhich the annular portion 8 of the conductor 8 extends is perforated topermit ready passage of the air into the conductor 7.

To the middle portion of the perforated plate 13 is secured the loweropen end of the tubular member 9 which is closed at its upper end.Through the side wall of the receptacle 1 extends another tubular member10 which is secured at its inner end into the side of the upper end ofthe tubular member 9, thus securing the plate 13 and the float mountedthereon at the lower portion of the receptacle. The tubular member 10 issecured in position by an elbow 11 which is connected at its outer end.by means of a flexible conductor 12, with the normally lower end of theannular portion of the conductor 8. Thus an air passage is providedbetween the hot air conductor 8., through the conductor 12, the elbow11, and the tubular members 10 and 9 to the bottom of the receptacle 1underneath the perforated plate 13. The conductor 12 is preferably madeflexible to adapt the carburetor to different makes of vehicles in whichthe exhaust manifolds or pipes are variously spaced.

The opposite extended end of the air conductor 7 is connected with theintake manifold 23 of the engine.

Intermediate the ends and in the wall at the lower side of the airconductor 7 is provided an orifice or passage 7 which connects theinterior of the receptacle 1 with the interior of the air conductor 7.At the inner side of the cover 2, through which the passage 7 extends,is provided a check valve 16 which consists of a casing 16 secured to alug on the inner side of the cover, and a ball 16" within the casing.This check valve is so constructed as to prevent any backfire throughthe intake manifold 23 of the engine to ignite the charge of fuel withinthe receptacle 1. Through the air conductor 7 extends a needle valve 17which is adapted to seat against a seat at the upper end of the passage7.

The portion of the air conductor 7 intermediate the orifice or passage 7and the perforated end thereof on which the air conductor 8 is mounted,is considerably reduced substantially forming a Venturi tube to increasethe vacuum at the orifice or passage 7, as the air from the conductor 8is drawn into the intake manifold 23. In this reduced portion of the airconductor 7, indicated by 7 in Fig. l, is mounted a butterfly valve 15,the rod of which extends upwardly through the wall of the air conductorand is provided at said upwardly extended end with an enlarged portionwhich is provided at its upper end with a laterally extending arm 15 towhich is pivotally connected the one end of the choke rod 2 1.

In the portion of the air conductor 7 between the orifice or passage 7and the intake manifold 23 is mounted another butterfly alve 14 which isprovided at the upper end of its control rod, extending through the wallof said conductor, with an actuating arm 25 to the outer end of which ispivotally con nected the control rod 26, as in the conventionalconstruction.

The arm 25 is provided at its connection with the rod of the butterflyvalve 14: with a short arm 25 which extends at an angle with the mainarm 25. The outer end of the arm 25 is pivotally connected by means of aresiliently extensible link with the outer end of an extensible arm 27in the form of a screw, which is adjustably secured in the enlargedportion 15 of the butterfly valve 15 and locked relatively thereto bymeans of a nut 28. The end of the extensible link 29. The extensiblelink consists of link members 30 and 31, the former pivotally connectedwith the arm and the latter with the screw 27. The free end of the linkmember is provided with a tubular portion -30 into which extends thefree end of the link member 31. lVithin the tubular portion 3O andbetween a shoulder at the end of the link member 30 and a head at theend of the link member 31 is positioned a compression spring 32 whichtends to contract said link members.

Thus, it will be seen that as the arm 25 is rotated clockwise to closethe butterfly valve 14, the butterfly valve 15 is closedproportionately, the proportion being easily varied by the adjustment ofthe arm or screw 27 relatively to the enlarged portion 15 of thebutterfly valve 15. The resiliently extensible link described permits ofthe rotation of the butterfly valve 15, by the arm 15 independently ofthe butterfly valve 14, thus serving as an independent choke valve.

When the engine is running at low speed the amount of air drawn throughthe valve 15 will be proportionally low and in order to preserve thecorrect mixture, the pressure difference between conductors 8 and 7 mustbe held at a suitable value. This is automatically attained by causingthe valve 15 to be closed with valve 14. By suitable adjustment of thesetting of valve 15, the pressure difference between conductors 8 and 7is maintained at the desired value, this pres sure difference causingthe proper flow of air through the receptacle 1.

The valve means for supplying additional air to the vaporized fuel inthe receptacle above the normal level of liquid fuel therein ispreferably connected with the upper end of the air tube 9 within thereceptacle and consists of a cone-shaped or tappet valve member 34preferably provided with longitudinal stems extending to either sidethereof, the inner stem being reciprocally mounted in'the wall of thetube 9 as shown in Fig. 4 of the drawings. The cone portion of the valvemember is adapted to seat in a boss extending outwardly from the tube.Around said boss is screwably secured a skeleton valve-stemsupportingbracket 35 provided with a guide portion at its outer end. In this guideportion is reciprocally mounted the other outwardly extending stem ofthe valve member, thus retaining the valve portion thereof in alinementwith its seat. Between the valve or cone portion of the valve member andthe guide portion of the bracket 35 is positioned a compression springfor holding the valve portion towards its seat.

With the valve means described above,

which may be either connected with a source of hot air through the tube9 or directly with the atmosphere through the wall of the receptacle 1,the vaporized fuel within the receptacle 1 is mixed with a small amountof air before leaving said receptacle through the passage 7 where themixture is again mixed with more air in the conductor 7.

When the valve 14 is closed to the idling speed of the engine, the valve15 is substantially wholly closed permitting only the gas in thereceptacle to be drawn into the engine, the tension of the spring 36being such as to provide a suitable mixture when the valve 15 is closed,as when throttling the engine, and also when the engine is running athigh speed, in which latter case the mixture in the receptacle is richerbut is mixed with more air when entering the conductor 7 Within and atthe upper portion of the receptacle 1 is positioned a multiple screenmember 18 which consists of an annular member 18 provided with fine wiremesh screens 18 and 18 at its upper and lower ends, the lower oneresting preferably at the upper end of the tube 9. As the air from thetube 9 passes to the lower end of the receptacle 1 and upwardly throughthe perforations in the plate 13 at a rapid rate of speed, beads of fuelare likely to be forced or drawn upwardly. The lower screen 18 stops thepassage of the beads upwardly into the air conductor 7, the screen 18causing a further breaking up of the fuel not vaporized, thus permittingonly the wholly vaporized fuel to pass through the passage 7 into theconductor 7 To the annular member 18 are secured lugs 1'8 which extendupwardly therefrom for more readily removing the screen member 18 fromthe receptacle 1.

It will be here noted that the screen member 18 or any other suitablescreen means may be eliminated if the receptacle 1 is considerablylengthened, which latter construction, however, is undesirable incertain carburetor constructions.

At the lower end of the receptacle 1 is provided a drain cock 33 fordraining and cleaning the carburetor when desired.

It will be noted with this construction of carburetor, an abnormalpercentage of water in the gasoline or other fuel can do no harm to thecarburetor and will not affect the smooth operation of the engine, forthe reason that the water is thoroughly vaporized and mixed with thefuel vapor. Other impurities or foreign matter in the gasoline or otherfuel, such as grit or heavier oils, will remain in the receptacle 1 andwill not be carried into the engine, reducing to a minimum injury to theengine parts and carbon deposits in the-cylinders of the engine.

Though I have shown and described a par ticular construction,combination and arrangement of parts and portions, I do not wish to belimited to this particular construction, combination and arrangement,but desire to include in the scope of my invention the construction,combination and arrangement substantially as set forth in the appendedclaims.v

Having thus described my invention, what I claim as new and desire tosecure by Letters Patent is:

1. In a carburetor structure having a fuel receptacle means, a fuelsupply conductor communicating with said fuel receptacle means and floatand valve means for controlling and regulating the entrance of fuel intosaid fuel receptacle, an air conductor having its intake end adjacent toan exhaust inanifold of a vehicle and its discharge end within saidreceptacle below the normal fuel level therein, a valve means mounted insaid air conductor within said receptacle above the normal fuel leveltherein communicating from said air conductor into said receptacle forequalizing the pressure therebetween and permitting the discharge ofexcess air from said air conductor into said receptacle and aiding theevaporation of fuel globules suspended within said receptacle, a secondair conductor connected with said first conductor and extending acrossthe top of said receptacle, a Venturi tube integral ith said second airconductor, a choke valve at the entering side of said Venturi tube, avalve controlled passage connecting said receptacle with said second airconductor approximately at the point of least pressure within said airconductor for drawing vaporized fuel from said receptacle.

2. In a carburetor structure having a fuel receptacle means, a fuelsupply conductor communicating with said fuel receptacle means and floatand valve means for controlling and regulating the entrance of fuel intosaid fuel receptacle, an air conductor having its intake end adjacent toan exhaust mani fold of a vehicle and its discharge end within saidreceptacle below the normal fuel level therein, a valve means mounted insaid air conductor within said receptacle above the normal fuel leveltherein communicating from said air conductor into said receptacle forequalizing the pressure therebetween and permitting the discharge ofexcess air from said air conductor into said receptacle and aiding theevaporation of fuel globules suspended within said receptacle, a secondair conductor connected with said first conductor and extending acrossthe top of said receptacle, a Venturi tube integral with said second airconductor, a choke valve at the entering side of said Venturi tube, avalve controlled passage connecting said receptacle with said second airconductor approximately at the point of least pressure within saidsecond air conductor for drawing vaporized fuel from said receptacle,

screen baflie means positioned in said receptacle above said valve meanstherein for further vaporizing the fuel within said receptacle andretarding movement thereof so as to mix with the air from said airconductor.

3. In a carburetor structure having a fuel receptacle means, a fuelsupply conductor communicating with said receptacle means and float andvalve means for controlling and regulating the entrance of fuel intosaid fuel receptacle, an air conductor having its intake end adjacent toan exhaust manifold of a vehicle and a discharge end within saidrcceptacle below the normal fuel level therein, a perforated partitionpositioned transversely in said receptacle, spaced slightly from theaottom thereof, and having a central opening for receiving the dischargeend. of said conductor for evenly distributing the air from said airconductor substantially radially over the bottom area of saidreceptacle, a second air conductor connected with said first conductorand extending across the top of said receptacle, a Venturi tube integralwith said second conductor, a choke valve at the entering side of saidVenturi tube, a valve controlled passage connecting said second airconductor with said receptacle approximately at the point of leastpressure in said second air conductor for drawing vaporized fuel fromsaid receptacle.

4. In a carburetor structure having a fuel receptacle means, a fuelsupply conductor communicating with said receptacle means and float andvalve means for controlling and regulating the entrance of fuel intosaid fuel receptacle, an air conductor having its intake end adjacent toan exhaust manifold of a vehicle and a discharge end within saidreceptacle below the normal fuel level therein, a perforated partitionpositioned transversely in said receptacle and spaced slightly from thebottom thereof and connected with the discharge en d of said conductorfor distributing the air from said air conductor over the bottom area ofsaid receptacle, a second air conductor connected with said firstconductor and extending across the top of said receptacle, a Venturitube integral with said second conductor, a choke valve at the enteringside of said Venturi tube, a valve controlled passage connecting saidsecond air conductor with said receptacle approximately at the point ofleast pressure in said second air conductor for drawing vaporized fuelfrom said receptacle, a valve means mounted in said first named airconductor within said receptacle above the normal fuel line thereofcommunicating between said first named air conductor and said receptaclefor equalizing the pressure therebetween, permitting the discharge ofexcess air from said air conductor into said receptacle and aid thevaporization of fuel globules suspended in said receptacle.

5. In a carburetor structure having a fuel receptacle means, a fuelsupply conductor communicating with said receptacle means and float andvalve means for controlling and regulating the entrance of fuel intosaid fuel receptacle, an air conductor having its intake end adjacent toan exhaust manifold of a vehicle and a discharge end within saidreceptacle below the normal fuel level therein, a perforated partitionpositioned transversely in said receptacle and spaced slightly from thebottom thereof and connected with the discharge end of said conductorfor distributing the air from said air conductor over the bottom area ofsaid receptacle, a second air conductor connected with said firstconductor and extending across the top of said receptacle, a Venturitube integral with said second conductor, a choke valve at the enter ingside of said Venturi tube, a valve cona trolled passage connecting saidsecond air conductor with said receptacle approximately at the point ofleast pressure in said second air conductor for drawing vaporized fuelfrom said receptacle, a valve means mounted in said first named airconductor within said receptacle above the normal fuel line thereofcommunicating between said first named air conductor and said receptaclefor equalizing the pressure therebetween, permitting the discharge ofexcess air from said first named air conductor into said receptacle andaiding the vaporization of fuel globules suspended in said receptacle, ascreen baffle means positioned within said receptacle above said Valvemeans for further vaporizing the fuel therein and retarding movementthereof so as to mix with the air from said air conductor.

In testimony whereof, I have hereunto set my hand at San Diego,California, this 11th day of March, 1925.

ARCHIE G. DOWVELL.

